Biden fractures foot playing with dog
Biden, who will become the oldest US president upon his January swearing-in, suffered the injury on Saturday with Major, one of his two German shepherds.
The president-elect's personal physician Kevin O'Connor initially said x-rays had not uncovered any "obvious fracture", but added that an additional CT scan would still be done.
That scan "confirmed hairline (small) fractures... in the mid-foot," O'Connor said in a subsequent statement released by Biden's office.
He added that the former vice president, who won election against Donald Trump in November, "will likely require a walking boot for several weeks".
With both Biden and Trump in their 70s, age was an issue in the presidential race, even if it often took a backseat to pressing matters like the Covid-19 pandemic.
"Get well soon!" Trump said on Twitter, in a retweet of an NBC video showing Biden leaving an orthopedic office.
Trump's health was briefly of intense concern when he caught Covid-19, but the president resumed campaigning after getting a series of treatments - including an experimental antibody cocktail.
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Trump, a famously finicky germophobe, was the first president in over a century to not have a dog.
The Bidens fostered and then adopted Major in 2018, while Champ has been with the family since 2008.